Production of heterophasic polymers in gas or slurry phase

Abstract

Methods for the production of heterophasic polymers in gas and slurry phase polymerization processes, and polymer compositions made therefrom, are disclosed herein.

What is claimed is: 
     
       1. A method for making a heterophasic polymer, the method comprising:
 a. contacting a single-site catalyst precursor, an activator, and a support to produce a catalyst system, wherein the support comprises silica and is characterized by an average surface area of from 400 m 2 /g to 800 m 2 /g; 
 b. contacting a monomer and optionally a comonomer in at least one gas or slurry phase reactor with the catalyst system under polymerization conditions comprising a first molar ratio of monomer to comonomer of from 90:10 to 100:0, to produce a porous matrix phase that, when comonomer is present, comprises a random statistical distribution of comonomer units; 
 c. adjusting, in the presence of the matrix phase, the polymerization conditions to a second molar ratio of monomer to comonomer of from 90:10 to 10:90 to produce a fill phase at least partially filling pores in the matrix phase; and 
 d. recovering a reactor effluent comprising a granular heterophasic polymer. 
 
     
     
       2. The method of  claim 1 , wherein the catalyst system comprises a support having:
 an average pore diameter of from 60 to 200 Angstrom; 
 at least 20% of the incremental pore volume comprised of pores having a pore diameter larger than 100 Angstrom; and 
 an activator comprising aluminoxane, wherein the aluminoxane loading is at least 7 mmol Al/g silica. 
 
     
     
       3. The method of  claim 1 , wherein the contacting in b) and the adjusting in c) occur in a single reactor. 
     
     
       4. The method of  claim 3 , wherein the single reactor is a gas phase fluidized bed reactor or a single tank autoclave reactor or a loop reactor operating in slurry phase. 
     
     
       5. The method of  claim 1 , wherein the contacting in b) occurs in at least one first reactor and the adjusting in c) occurs in at least one second reactor. 
     
     
       6. The method of  claim 1 , wherein the contacting in b) occurs in at least one single tank autoclave reactor or a loop reactor operating in slurry phase, and the adjusting in c) occurs in at least one gas phase fluidized bed reactor. 
     
     
       7. The method of  claim 1 , wherein the contacting in b) occurs in at least one gas phase fluidized bed reactor, and the adjusting in c) occurs in at least one single tank autoclave reactor or at least one loop reactor operating in slurry phase. 
     
     
       8. The method of  claim 1 , wherein comonomer is present and the monomer is propylene and the comonomer is ethylene. 
     
     
       9. The method of  claim 1 , wherein the polymerization conditions comprise a temperature from about 10° C. to less than 135° C. 
     
     
       10. The method of  claim 1 , wherein the single-site catalyst precursor comprises a compound represented by the formula:
   (Cp) m R A   n M 4 Q k    
 wherein: 
 each Cp is a cyclopentadienyl, indenyl, or fluorenyl moiety substituted by one or more hydrocarbyl radicals having from 1 to 20 carbon atoms; 
 R A  is a bridge between two Cp rings; 
 M 4  is a transition metal selected from group 4 or 5; 
 Q is a hydride or a hydrocarbyl group having from 1 to 20 carbon atoms, an alkenyl group having from 2 to 20 carbon atoms, or a halogen; 
 m is 1, 2, or 3, with the proviso that if m is 2 or 3, each Cp may be the same or different; 
 n is 0 or 1, with the proviso that n=0 if m=1; and 
 k is such that k+m is equal to the oxidation state of M 4 , with the proviso that if k is greater than 1, each Q may be the same or different. 
 
     
     
       11. The method of  claim 1 , wherein the single-site catalyst precursor comprises a compound represented by the formula:
   R A (CpR″ p )(CpR* q )M 5 Q r  
 
 wherein: 
 each Cp is a cyclopentadienyl moiety or substituted cyclopentadienyl moiety; 
 each R* and R″ is a hydrocarbyl group having from 1 to 20 carbon atoms and may be the same or different; 
 p is 0, 1, 2, 3, or 4; 
 q is 1, 2, 3, or 4; 
 R A  is a bridge between the Cp moieties; 
 M 5  is a group 4, 5, or 6 metal; 
 Q is a hydrocarbyl radical having 1 to 20 carbon atoms or is a halogen; 
 r is s minus 2, where s is the valence of M 5 ; 
 (CpR* q ) has bilateral or pseudobilateral symmetry, wherein R* q  is selected such that (CpR* q ) forms a fluorenyl, alkyl substituted indenyl, or tetra-, tri-, or dialkyl substituted cyclopentadienyl radical; 
 (CpR″ p ) contains a bulky group in one and only one of the distal positions, wherein the bulky group is of the formula AR W   V ; and 
 A is chosen from group 4 metals, oxygen, or nitrogen, R W  is a methyl radical or phenyl radical, and v is the valence of A minus 1. 
 
     
     
       12. The method of  claim 1 , wherein the single-site catalyst precursor comprises a compound represented by the formula: 
       
         
           
           
               
               
           
         
         wherein: 
         M is a metal from group 4, 5 or 6; 
         T is a bridging group; 
         each X is, independently, an anionic leaving group; 
         each R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , and R 13  is, independently, halogen atom, hydrogen, hydrocarbyl, substituted hydrocarbyl, halocarbyl, substituted halocarbyl, silylcarbyl, substituted silylcarbyl, germylcarbyl, substituted germylcarbyl substituent or a —NR′ 2 , —SR′, —OR′, —OSiR′ 3  or —PR′ 2  radical, wherein R′ is one of a halogen atom, a C 1 -C 10  alkyl group, or a C 6 -C 10  aryl group. 
       
     
     
       13. The method of  claim 1 , wherein the single-site catalyst precursor comprises a compound represented by the formula: 
       
         
           
           
               
               
           
         
         wherein: 
         M is a group 4 transition metal; 
         X 1  and X 2  are, independently, a univalent C 1  to C 20  hydrocarbyl radical, a C 1  to C 20  substituted hydrocarbyl radical, a heteroatom or a heteroatom-containing group, or X 1  and X 2  join together to form a C 4  to C 62  cyclic or polycyclic ring structure; 
         each R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , and R 10  is, independently, a hydrogen, a C 1  to C 40  ydrocarbyl radical, a substituted C 1  to C 40  hydrocarbyl radical, a heteroatom, a heteroatom-containing group or each R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , and R 10  is a functional group comprising of elements from groups 13 to 17, wherein two or more of R 1  to R 10  optionally independently join together to form a C 4  to C 62  cyclic or polycyclic ring structure; 
         Q is a neutral donor group; 
         J is a C 7  to C 60  fused polycyclic group, optionally comprising up to 20 atoms from groups 15 and 16, where at least one ring is aromatic and where at least one ring, which may or may not be aromatic, has at least 5 members; 
         G is, independently, as defined for J or a hydrogen, a C 1  to C 60  hydrocarbyl radical, a substituted hydrocarbyl radical, a heteroatom, or a heteroatom-containing group, or G optionally forms a C 4  to C 60  cyclic or polycyclic ring structure with R 6 , R 7 , or R 8 , or a combination thereof; and 
         Y is a divalent C 1  to C 20  hydrocarbyl or a substituted divalent hydrocarbyl group. 
       
     
     
       14. The method of  claim 1 , wherein the support comprises agglomerates of primary particles. 
     
     
       15. The method of  claim 14 , wherein the primary particles have an average particle size of from 0.01 μm to 20 μm and the agglomerates have an average particle size of 30 to 200 μm. 
     
     
       16. The method of  claim 14 , wherein the primary particles have a narrow particle size distribution, characterized by a D10 not smaller than 80% of D50 and a D90 not larger than 120% of D50. 
     
     
       17. The method of  claim 1 , wherein the support is spray dried prior to the contacting in b). 
     
     
       18. The method of  claim 1 , wherein carbon black is not present during the contacting in b) and the adjusting in c). 
     
     
       19. The method of  claim 1 , wherein the heterophasic polymer comprises 7 to 85 wt % fill phase, based on the total weight of the matrix and fill phases. 
     
     
       20. The method of  claim 1 , wherein the heterophasic polymer is free-flowing. 
     
     
       21. The method of  claim 1  wherein the granular heterophasic polymer comprises:
 a matrix phase comprising: 
 at least 90 mol % monomer and from 0 to 10 mol % comonomer, based on the total moles of monomer and comonomer the matrix phase; 
 a porosity of 20% or more as determined by mercury intrusion porosimetry; 
 a median pore diameter of 165 μm or less as determined by mercury intrustion porosimetry; 
 a random statistical distribution of monomer units; and 
 a composition distribution breadth index of 50% or more; and 
 a fill phase at least partially filling pores in the matrix phase, wherein the fill phase is from 12 to 90 wt % of the polymer, based on the total weight of the matrix and fill phases; and wherein the monomer to comonomer molar ratio in the fill phase is from 80:20 to 20:80. 
 
     
     
       22. The method of  claim 21 , wherein the polymer is granular and free-flowing, and part of a reactor effluent withdrawn from a reactor. 
     
     
       23. The method of  claim 21 , wherein the monomer is propylene and the comonomer is ethylene or the monomer is ethylene and the comonomer is at least one C 3  to C 12  olefin and/or diene. 
     
     
       24. The method of  claim 21 , wherein the polymeris a copolymer and has a bimodal composition distribution in a GPC-IR trace. 
     
     
       25. The method of  claim 21 , wherein the matrix phase comprises polyethylene homopolymer or syndiotactic polypropylene. 
     
     
       26. The method of  claim 21 , wherein the fill phase comprises EPDM. 
     
     
       27. A method for making a heterophasic polymer, the method comprising:
 a. contacting a single-site catalyst precursor, an activator, and a support to produce a catalyst system, wherein the support comprises silica and is characterized by an average surface area of from 400 m 2 /g to 800 m 2 /g; 
 b. contacting a monomer and a comonomer in at least one gas or slurry phase reactor with the catalyst system under polymerization conditions comprising a first molar ratio of monomer to comonomer of from 90:10 to 100:0, to produce a porous matrix phase comprising a random statistical distribution of comonomer units; 
 c. adjusting, in the presence of the matrix phase, the polymerization conditions to a second molar ratio of monomer to comonomer of from 90:10 to 10:90 to produce a fill phase at least partially filling pores in the matrix phase; and 
 d. recovering a reactor effluent comprising a granular heterophasic polymer. 
 
     
     
       28. The method of  claim 21 , wherein the polymer has a bimodal molecular weight distribution. 
     
     
       29. The method of  claim 21 , wherein the polymer is a copolymer and has a bimodal composition distribution in a GPC-IR trace and a bimodal molecular weight distribution. 
     
     
       30. The method of  claim 1 , wherein comonomer is present and the monomer is ethylene and the comonomer is at least one C 3  to C 12  olefin. 
     
     
       31. The method of  claim 1  wherein the granular heterophasic polymer comprises:
 a matrix phase comprising: 
 at least 90 mol % monomer and from 0.1 to 10 mol % comonomer, based on the total moles of monomer and comonomer the matrix phase; 
 a porosity of 20% or more as determined by mercury intrusion porosimetry; 
 a median pore diameter of 165 μm or less as determined by mercury intrustion porosimetry; 
 a random statistical distribution of monomer units; and 
 a composition distribution breadth index of 50% or more; and 
 a fill phase at least partially filling pores in the matrix phase, wherein the fill phase is from 12 to 90 wt % of the polymer, based on the total weight of the matrix and fill phases; and wherein the monomer to comonomer molar ratio in the fill phase is from 80:20 to 20:80. 
 
     
     
       32. The method of  claim 1 , wherein the single-site catalyst precursor comprises one or more of:
 dimethylsilylene-bis(2-cyclopropyl-4-phenylindenyl)zirconium dichloride; dimethylsilylene-bis(2-cyclopropyl-4-phenylindenyl)hafnium dichloride; 
 dimethylsilylene-bis(2-methyl-4-phenylindenyl)zirconium dichloride; 
 dimethylsilylene-bis(2-methyl-4-phenylindenyl)hafnium dichloride; 
 dimethylsilylene-bis(2-methyl-4-orthobiphenylindenyl)hafnium dichloride; 
 dimethylsilylene-bis(2-methyl-4-orthobiphenylindenyl)zirconium dichloride; 
 dimethylsilylene-(2-cyclopropyl-4-orthobiphenylindenyl)(2-methyl-4-3′,5′-di-t-butylphenylindenyl)hafnium dichloride; 
 dimethylsilylene-(2-cyclopropyl-4-orthobiphenylindenyl)(2-methyl-4-3′,5′-di-t-butylphenylindenyl)zirconium dichloride; 
 dimethylsilylene-(2-isopropyl-4(4-t-butyl)phenyl)indenyl) (2-methyl-4-phenyl indenyl) zirconium dichloride; 
 dimethylsilylene-(2-isopropyl-4(4-t-butyl)phenyl)indenyl) (2-methyl-4-phenyl indenyl) hafnium dichloride; 
 dimethylsilylene-(2-isopropyl-4(4-t-butyl)phenyl)indenyl) (2-methyl, 4-t-butylindenyl) zirconium dichloride; 
 dimethylsilylene-(2-isopropyl-4(4-t-butyl)phenyl)indenyl) (2-methyl, 4-t-butylindenyl) hafnium dichloride; 
 dimethylsilylene-(2-isopropyl-4(4-t-butyl)phenyl)indenyl) (2-methyl-4-phenylindacenyl) zirconium dichloride; 
 dimethylsilylene-(2-isopropyl-4(4-t-butyl)phenyl)indenyl) (2-methyl-4-phenylindacenyl) hafnium dichloride; 
 dimethyl silylene (4-o-biphenyl-2-(1-methylcyclohexyl)methyl-indenyl) (4-(3,5-di-tert-butylphenyl)-2-methyl-indenyl) zirconium dichloride; and 
 dimethyl silylene (4-o-Biphenyl-2-(1-methylcyclohexyl)methyl-indenyl) (4-(3,5-di-tert-butylphenyl)-2-methyl-indenyl) hafnium dichloride; where, in alternate embodiments, the dichloride in any of the compounds listed above may be replaced with dialkyl, dialkaryl, diflouride, diiodide, or dibromide, or a combination thereof 
 
     
     
       33. The method of  claim 27 , wherein the single-site catalyst precursor comprises one or more of:
 dimethylsilylene-bis(2-cyclopropyl-4-phenylindenyl)zirconium dichloride; dimethylsilylene-bis(2-cyclopropyl-4-phenylindenyl)hafnium dichloride; 
 dimethylsilylene-bis(2-methyl-4-phenylindenyl)zirconium dichloride; 
 dimethylsilylene-bis(2-methyl-4-phenylindenyl)hafnium dichloride; 
 dimethylsilylene-bis(2-methyl-4-orthobiphenylindenyl)hafnium dichloride; 
 dimethylsilylene-bis(2-methyl-4-orthobiphenylindenyl)zirconium dichloride; 
 dimethylsilylene-(2-cyclopropyl-4-orthobiphenylindenyl)(2-methyl-4-3′,5′-di-t-butylphenylindenyl)hafnium dichloride; 
 dimethylsilylene-(2-cyclopropyl-4-orthobiphenylindenyl)(2-methyl-4-3′,5′-di-t-butylphenylindenyl)zirconium dichloride; 
 dimethylsilylene-(2-isopropyl-4(4-t-butyl)phenyl)indenyl) (2-methyl-4-phenyl indenyl) zirconium dichloride; 
 dimethylsilylene-(2-isopropyl-4(4-t-butyl)phenyl)indenyl) (2-methyl-4-phenyl indenyl) hafnium dichloride; 
 dimethylsilylene-(2-isopropyl-4(4-t-butyl)phenyl)indenyl) (2-methyl, 4-t-butylindenyl) zirconium dichloride; 
 dimethylsilylene-(2-isopropyl-4(4-t-butyl)phenyl)indenyl) (2-methyl, 4-t-butylindenyl) hafnium dichloride; 
 dimethylsilylene-(2-isopropyl-4(4-t-butyl)phenyl)indenyl) (2-methyl-4-phenylindacenyl) zirconium dichloride; 
 dimethylsilylene-(2-isopropyl-4(4-t-butyl)phenyl)indenyl) (2-methyl-4-phenylindacenyl) hafnium dichloride; 
 dimethyl silylene (4-o-biphenyl-2-(1-methylcyclohexyl)methyl-indenyl) (4-(3,5-di-tert-butylphenyl)-2-methyl-indenyl) zirconium dichloride; and 
 dimethyl silylene (4-o-Biphenyl-2-(1-methylcyclohexyl)methyl-indenyl) (4-(3,5-di-tert-butylphenyl)-2-methyl-indenyl) hafnium dichloride; where, in alternate embodiments, the dichloride in any of the compounds listed above may be replaced with dialkyl, dialkaryl, diflouride, diiodide, or dibromide, or a combination thereof. 
 
     
     
       34. The method of  claim 12 , wherein the T is represented by R′ 2 C, R′ 2 Si, or R′ 2 Ge, where each R′ is, independently, hydrogen or a C 1  to C 20  containing hydrocarbyl, substituted hydrocarbyl, halocarbyl, substituted halocarbyl, silylcarbyl or germylcarbyl substituent, and optionally, two or more adjacent R′ may join to form a substituted or unsubstituted, saturated, partially unsaturated or aromatic, cyclic or polycyclic substituent. 
     
     
       35. The method of  claim 12 , wherein the T is CH 2 , CH 2 CH 2 , C(CH 3 ) 2 , SiMe 2 , SiPh 2 , SiMePh, (Si(CH 2 ) 3 ), (Ph) 2 C, (p-(Et) 3 SiPh) 2 C, (Si(CH 2 ) 4 ), or Si(CH 2 ) 5 .